Hard disks are typically classified into mechanical hard disks HDD and solid-state hard disks SSD. A mechanical hard disk is a common traditional hard disk which supports overwriting, and thus the deleted data, if marked, may be readily recovered before they are covered by new data. While a solid-state hard disk is formed of an array of solid-state electronic storage chips, and composed of control units and storage units, it does not support overwriting, and must be erased in advance. This is known as trash recycling.
Data recycling is primarily recycling with respect to suitable blocks selected from blocks comprising invalid data, wherein the blocks reside in a memory bank. The memory bank comprises multiple blocks, and each block comprises multiple pages. The valid data is stored in an update block, and the data in the original block can be erased to increase the number of empty blocks to achieve the objective of releasing usable spaces in order to have sufficient blocks for use in data writing.
Currently, the commonly used method is: taking into overall consideration of the number of erasing times, write times, and the number of valid pages, secondly, defining a loss function, and finally, taking the block with the maximum value of the loss function as the block for use in data recycling, that is, the storage unit for data recycling. However, since only one block can be selected for data recycling each time in the data recycling process, it results in resource wasting, increased data recycling numbers, and decreased efficiency.